Our favorite physicians and surgeons from seattle have been saving lives for 199 episodes. Tonight's "grey's anatomy," love it, episode 200. We're going to talk to one of the stars, sandra oh, in a moment. And first, a walk down memory lane, with abc's chris connelly. Reporter: Through 199 episodes of "grey's anatomy," meredith grey and the doctors of seattle grace, have saved lives and epically pursued love. So, pick me. Choose me. Love me. Reporter: Meredith and McDREAMY. Their m.D. Heart, filling with romance. I believe we can be extraordinary together, rather than ordinary apart. Reporter: Passion, leading to their simple wedding on a post-it. This is our wedding, a post-it? Uh-huh. Would you sign that paper? Reporter: Amid all ardor, a few couples flat lined, as well. He's gone. Take it off. Take it off. Reporter: Dr. Christina yang, left at the altar. The fiancee of dr. Izzy, gone. And now, I lost him. Reporter: It was a death shonda rhimes was the hardest of all. A few episodes sent vital signs soaring, like this post super bowl multiparter, with a crisis really was the bomb. As any greys fan will tell you, try to breathe for a moment and you can't. For "good morning america," chris connelly, abc news, los angeles. So many moments over the years. And we're excited to have one of "grey's anatomy" original six with us. Do the honors, sam. Sandra oh. Good morning. Were you speaking through the door again? Nice to see you. Congratulations. Nice to meet you. How are you? I'm such a fan. Come over here. Right here. Very good. There's the latte? We're looking at the retrospective. I was looking at that, as well. Can't believe it's the 200th episode. This is quite a milestone. It's ten years. We're well into our tenth season. And you know, just reflecting on it. It's so rare in our industry that you are able to have a job that will last you this long. But for me, to be able to play a character for ten seasons is extraordinary. Creatively, it's extraordinary. And have the core group stay together as you have. You came bearing gifts. We have a clip from tonight's episode. You're at a fund-raiser. And someone's giving you a hard time. Let's take a look. That's your fifth one. Who are you? My mom? Glass of chardonnay. Abc interactive. Got him on the ropes. Another zero added to the check. At the end of the night. That sounds wrong. This is a wild west. Love your sass. One of the six original cast members. That's a rarity. Yeah. We've had quite a bit of episodes in the beginning of this season. And I love that scene because it was a vintage christina/alex scene, where she's just full-on And he's like not really caring. It's dynamic. I wish I had a whisky soda for this question. How did you come to the decision to leave? Well -- it's mostly a creative one. Again, the rare opportunity of being able to fulfill and grow a character for ten seasons actually growing her, I swear, in real lifetime. And you see people going through relationships. Her growth as a human being, as a friend. And there just comes a point, as an artist, where you feel like your work is done. And it's really that. You say a friend. Shonda rhimes, somebody who has spoken of you, spoke of your audition as a big moment in her life. What has it been like, then, to work with somebody like shonda and come to this decision perhaps together? It's still ongoing. It's extremely emotional for both of us. Every so often, we'll check in. And I'll go into her office and cry. About what, we don't know. And I'm eager to hear about her process. I'm really lucky to -- there's something about for me, at least for me, I'm connected to her through christina. And there are times -- mostly the times when we have not gotten along, where we clashed over stuff, that we learned over and over again. It happens after ten years. After you clash and clash, you know a third great thing is about to come out of it. That's trust. And we've hit that over and over again. As we say good-bye, we have this for you. Thank you. The 200th episode of "grey's anatomy," tonight, 8:00 eastern. Thank you. 9:00, 8:00 central, here on abc. I love it. What a week it's been for our katy perry "roar" contest.

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